away. >> reporter: in this case floating away. >> exactly. >> reporter: that water came from this dam officials decided to open overnight to avoid a possible breach. from the plains to the northeast, violent wet weather, 159 reported tornados in 15 states. in new york city wednesday, the tenth rainiest day on record, close to five inches. still, that's nowhere near the eye-popping totals across the southeast. 11 inches in mobile and pensacola, 20 inches since monday. at one point, almost half a foot of water in a a single hour. investigators are looking into whether flooding was a factor last night. two inmates killed, 180 others injure when had a blast rocked the complex shaking houses up to three miles away. so much rain fell in philadelphia that a major river crested higher than it did during super storm sandy. >> just because the rain has stopped, just because it appears, of course, that the rivers or streams are reseeding, unfortunately, we can get lulled into a very false sense of security.